This important species is in danger because people wrongly believe its horns have medicinal properties

Once widespread across Asia and Africa’s savannas and tropical forests, rhinos are now being poached to extinction because many believe that their horns are a powerful medicine. And as a keystone species, these giants play an important role in balancing ecosystems.

Of all the rhino species, northern white rhinos are the hardest hit. There’s only four individuals left in the entire world, and all are in captivity, according the NGO Save the Rhino.

The culprit? The hugely profitable black-market rhino horn trade — and the demand comes from East Asia, where powdered rhino horn is used as a traditional medicine.

According to The Atlantic, skyrocketing demand in Vietnam now means that quality rhino horns can sell for up to $100,000 per kilogram (USD) on the black market.

That’s an astronomical increase since the early 1990’s, when a rhino horn could fetch only around $250 to 500 on the black market. Even 25 years ago, the price of rhino horns was too low for poaching to be a real problem, according to data from the IUCN African rhino specialist group.

Now, because there’s so much money to be made by selling rhino horns, poaching is quickly becoming a major threat to all rhino species long-term survival.

In South Africa — where the savanna ecosystem has supported healthy rhino populations for millennia — only 13 rhinos were poached in 2007. By 2014, that number had skyrocketed to 1,215, according to data from the South African Department of Environmental Affairs. That’s out of a total population of approximately 4,800 black rhino and 20,000 white rhino in South Africa, according to the WWF.

While there’s a rich tradition of rhino horn carving in both Vietnam and China — going as far back as the 7th century according to the US Fish and Wildlife Service — the demand now is being driven by the somewhat bizarre notion that rhino horn has medicinal and curative properties.

As incomes rise in Vietnam, the newly-minted wealthy class is willing to throw down serious cash for black-market rhino horns, which they believe can do everything from cure cancer to alleviate hangovers, according to the New Scientist.

“Eastern medicine believes that rhino horn can filter out toxins,” Nguyen Van Nhuong, a Vietnamese cancer patient, told a Vice crew that investigated the rhino horn trade in 2014. “Therefore, it can detoxify the body. That’s the effect of rhino horn.”

While traditional medicine in China and Vietnam has long touted the benefits of rhino horn, multiple studies carried out since 1983 found little-to-no evidence that rhino horns are an effective medicine.

Arne Schiotz of World Wildlife Fund put it like this: “Rhino horn is of no use to anyone except the original owner. You would get the same effect from chewing your own fingernails,” as National Geographic reported.

Aside from spreading medicinal myths, the environmental damage from losing rhinos could be immeasurable. As a large, keystone species (“megaherbivore“), the removal of rhinos from an ecosystem could have a huge downstream effect, according to Conservation Magazine.